Starring: Andrew DunnCaroline Lee-JohnsonMalcolm StorryAnthony Valentine

The Knock is a British television drama series, created by Anita Bronson and broadcast on ITV from 1994 to 2000, which portrayed the activities of customs officers from Her Majesty's Customs and Excise. The series derived its name from the distinctive "Knock knock knock" command used over the radio to synchronise a raid.